A couple gets their hands dirty in Brooklyn by rehabilitating a 19th-century tenement to reveal decades of layers and scores of possibilities. The wall separating the two railroad apartments would be torn down, creating a 1,250-square-foot space, with a bathroom and a combined bedroom and dressing room set off from an open area for cooking, eating, and entertaining.

Alex Gil and Claudia DeSimio created a duplex in an apartment building where they’d been renting for years in Brooklyn, New York, and set to work gutting the interior and adding a new rooftop addition clad in panels of Cor-Ten steel.